<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
		<style type="text/css">
			.first{
				width: 200px;
				height: 200px;
				background-color: red;
				margin-top: 30px;
				/* padding-top: 1px; */
				
			}
			.second{
				width: 100px;
				height: 100px;
				background-color: green;
				margin-top: 20px;
			}
		</style>
	</head>
	<body>
		<div class="first">
			<div class="second"></div>
		</div>	
		
	</body>
</html>
